This invention relates to display sign assemblies of the type having flexible sheet display faces, and more particularly to a display sign assembly of this type which may be readily constructed from relatively inexpensive elements and which permit the flexible faces to be stretched in a simplified manner.
The development of outdoor display signs for identifying and promoting places of business, such as motels, restaurants and the like, has progressed from painted sign boards, "neon" signs, glass or similar transparent face displays through rigid plastic panelling until the development of a stretchable fabric-like material. This development is ablely traced in the disclosure of Brooks U.S. Pat. No. 4,265,039. The advantages of the stretchable fabric-like material, which is marketed by 3M Company under the trademark PANAFLEX and by Signtech, Inc. under the trademark FLEXFACE includes its ability to flex under high wind conditions so as not to burst or blow-out of the cabinet in which it is mounted which was a problem of the rigid facing.
Because of the necessity for tensioning the stretchable material, the known display signs have utilized aluminum extrusions having various cross sectional configurations and fabric tensioning devices in combination therewith. Examples of display signs utilizing such extrusions include the aforesaid Brooks patent and Gandy U.S. Pat. No. 4,452,000. Even before the development of the flexible face signs, extruded aluminum sign frames were extensively employed. Examples of display signs incorporating such extrusions include Brooks U.S. Pat. No. 4,007,552; Kloke U.S. Pat. No. 4,267,657 and Gandy U.S. Pat. No. 4,380,880. Obviously, specialized extrusions result in expensive sign fabrication, and because of the fabric stretching mechanisms utilized with such extrusions the labor costs for precisely tensioning the fabric in the display sign frame and within the display sign cabinet is substantial.
The extruded frame constructions stretch the flexible sheet material by wrapping the material about a plurality of retainer bars or wedges, or the like, spaced successively about the peripheral length of the extrusion, generally approximately every 12 inches. In the aforesaid Gandy U.S. Pat. No. 4,452,000 retainer bars are individually adjustably moved by bolt members while in Brooks U.S. Pat. No. 4,265,039 extruded levers receive cylindrical wedges and the levers are individually pivoted. In either case the retainers or wedges are moved into and relative to recesses formed in the extrusions for this purpose. Since the flexible sheet is wrapped about the bars or wedges it is incrementally stretched as each of the retaining bars or wedges move relative to the extrusion.
Additionally, the extruded cabinet and frames require specialized corner pieces which must be specially cast so as to fit the extrusions.
When retrofitting signs having the extruded components, the sign frame must be removed, the face disconnected by means of the retainers or wedges, a new face installed by individually securing and adjusting the multiplicity of retainers or wedges and reattaching the frame. Alternatively a workman must enter the cabinet and disconnect each of the retaining members or wedges from its connection with the facing, and thereafter individually reattaching the retainers or wedges to the facing, and adjusting each one until the tension on the face is proper. Clearly this is a tedious and expensive labor intensive process. Moreover, when retrofitting a flexible face sign in place of a rigid face sign the extrusion must be assembled so as to exactly fit the exterior of the preexisting cabinet. This usually requires that a substantial number of screws being clearly visible on the exterior of the cabinet detracting from the aesthetics of the sign.
The extruded constructions therefore have a number of deficiencies not the least of which is that they must be individually fitted to preexisting cabinets when retrofitting, and additionally the facing has to be stretched separately by independent stretching members disposed about the periphery thereof. All of the above mentioned factors obviously add to the cost of replacing a display sign. Additionally, display signs constructed from extrusions do not have the strength and durability of the steel angle or channel member framework signs which were the mainstay of the earlier rigid face signs since the extrusions tend to bend, and a substantial amount of brace-work must be included to prevent twisting under high wind conditions.